sented in July 1909 a second military plane, which filled their contract with the Signal Corps.

Recently the Corps has acquired Army television responsibility. The allied techniques of photography, television, radar, infrared, and other devices have combined to produce the

Army's Combat Surveillance program, a new Signal Corps responsibility. In 1952 the Corps opened Fort Huachuca, Arizona, as the Army Electronic Proving Ground, where new methods and equipment embracing a wide span of communications-electronic activity are being tested.

MESSAGE CENTERS. The communications system serving any Army headquarters has its focus in the message center. A message center has the following functions

1. Handling all messages to or from the headquarters, except those transmitted direct by the originator or handled by military or civil post; and keeping records thereon.

2. Selecting the means of transmitting messages, checking on their flow, and reporting to the originator any undue delay in transmission.

3. Coordinating the means of communication and checking on their effectiveness.

4. Observing security regulations.

5. Keeping up-to-date information on where unit command posts are located and how to reach them.

6. Keeping the official time of headquarters.

RADIO NETS. Military radio sets are operated in "nets." Sets which can work together because of similar frequency settings, similar type of signal ("CW", "MCW" or "voice"), and similar type of modulation (FM or AM) are said to be capable of netting with each other. A net is formed when two or more stations operate on the same frequency and can intercommunicate. Each station has a call sign, which is periodically changed. In forming a net, definite procedures are required to adjust its equipment, control transmission, and clear the messages. There is a net control station (NCS), the duties of which are to open and close the net and maintain discipline within it. Sometimes an alternate control station (NCS 2) is desigated. Army units (for example, infantry, armored, and airborne divisions,

and many other larger and smaller commands) each have their characteristic nets or groups of nets, determined by the need which the elements composing the unit have to communicate with each other. These nets are of various types. Command nets connect the unit commander with his subordinate commanders. Reconnaissance and Surveillance nets are intended to give staff officers the information on which combat intelligence is based. A number of different support nets are needed: for example, to furnish firing data to gun batteries, to provide unit headquarters with channels for administrative communications, and so on.

COMMUNICATIONS

DISCIPLINE.

Since radio communications can be intercepted by the enemy, communications discipline and crytographic security are vital to prevent him from acquiring useful information by listening to radio traffic. Communications discipline involves the proper use of radio equipment, good net control, and the meticulous training of radio operators. It requires that operators use only the radio frequencies which have been allotted to them, and that they follow explicitly the details of the operating procedures which have been laid down for them. It involves careful monitoring of their radio transmissions. An important aspect of communications security is cryptosecurity, involving, for example. the proper use of codes and ciphers to deny the enemy any knowledge of the content of radio communications. Good cryptosecurity depends upon the use of approved cryptosystems, strict adherence to crypto operating instructions and procedures, the assignment of qualified and trained personnel to crypto duties, the

1

The Army Medical Service, as it is called today, traces its origin to the beginning of our national history. On 27 July 1775, on the recommendation of General George Washington, the Continental Congress created the first military-medical service. (Although it was termed "an Hospital" by the Congress, the service, not an institution, was meant.) But the service remained without a central organization until the appointment of General Joseph Lovell as first Surgeon General in 1818. Since that date the Office of The Surgeon General has had a continuous existence.

During the century prior to World War I the Army Medical Service adopted much of the organization and many of the practices which distinguish it today. New techniques and procedures were progressively adopted, based on wartime experience and the depressing story of unpreparedness told by disease and casualty rates.

Medical officers received military rank in 1847. Before the Mexican War the Surgeon General introduced a system of reporting cases, and began the series of annual statistical reports on the health of the Army. The war showed the need for adequate staffs of nonprofessional enlisted personnel to assist the surgeons-a need not fully met until 1887. The Civil War produced field hospitals, a better managed medical supply, and a better method of evacuating casualties from the battlefield. The Spanish-American War was an object lesson in the importance of preventive medicine and in the utility

of dentists and female nurses. A new program of disease prevention, together with the establishment of the Army Nurse Corps (1901), the Medical (officers) Reserve Corps (1908), the Dental Corps (1911), and the Veterinary Corps (1916), placed the Army Medical Service in a better state of preparedness for World War I than for any previous conflict.

The unprecedented size of the Army in that war, the remoteness of the battlefronts, the injuries from gas warfare, and the necessity of exploiting the new crop of medical specialists combined to create new problems which challenged the Medical Service's administrative and professional skill. To meet these demands, the Service conducted mass training for officers and enlisted men. It utilized motor transport in evacuating patients. It appointed top-ranking experts in the various specialties as consultants, made extensive use of mental testing, and set aside numerous hospitals for the treatment of particular diseases and injuries. In 1917 a Sanitary Corps was established; this is represented today by the Sanitary Engineering Section of the Medical Service Corps (established 1947). Medical statistics (see below) reflect the success of these efforts.

In World War II the Medical Service drew heavily on its World War I experience. However, many important changes in organization and methods were necessary to use the newer developments in medicine and to serve

an Army which was fighting a global war in every kind of physical environment. With a total strength of more than 600,000 (as compared to 340,000 in World War I) the Service added to and broadened its fields of activity. Typical of this expansion were the vastly enlarged program of preventive medicine, the increased use of psychiatry to prevent as well as to cure mental disorders, and the much greater emphasis on reconditioning physical and mental casualties for military duty. For the first time, also, the sulfa drugs and penicillin were employed in American war medicine and surgery, and important use was made of whole blood transfusions. Another new and important contribution to effective treatment was the rapid transport of patients by air.

During the war three new officer components were created: the Pharmacy Corps, the Physical Therapists, and the Dietitians. In 1947 these components were included in two new officer corps, the Medical Service Corps and the Women's Medical Specialist Corps. Legislation in 1955 opened the Women's Medical Specialist Corps and the Army Nurse Corps to men, and the name of the former was changed to the Army Medical Specialist Corps.

During the Korean War, with a total strength of approximately 107,000, the

Army Medical Service reduced morbidity and mortality to a new low by more effective preventive medicine, better treatment, and decreased delay before definitive surgery. Chloroquine suppression and primaquine treatment virtually solved the problem of malaria. Rapid helicopter evacuation to forward units which were equipped, staffed, and trained in such advanced techniques as neurological and vascular surgery markedly reduced loss of life and permanent disability. Increased use of whole blood, introduction of synthetic plasma volume expanders, and forward use of the artificial kidney were further adjuncts to better medical support. Improved handling of neuropsychological disorders was of particular value in reducing manpower losses in combat units. For the first time in modern warfare, body armor was used, and this resulted in the saving of many lives.

Since the end of the Korean War the Army Medical Service has declined in numbers (to approximately 47,000 officers and enlisted personnel as of July 1957). Its responsibilities are still global, however, reaching wherever American forces are stationed. To assure assistance from experts in the civilian medical profession, some 1,500 physicians are currently employed on a part-time basis as consultants to the Army Surgeon General.

The Army Surgeon General provides health services for the Army, and, as assigned, for the Navy and Air Force. He develops and supervises policies and plans; provides and conducts programs; establishes standards, technical procedures, organization and doctrine; and conducts medical research and development relating to the health of the Army. He develops, provides, and services medical material required by the Army, and, as assigned, for the Navy and Air Force and for foreign aid programs. He also prescribes the curricula at Army Medical Service schools and separate courses of instruction composed predominantly of medical professional material.

Certain elements of the Army Medical

Service are under the direct command of the Surgeon General. With respect to the others he exercises technical supervision.

AGENCIES NOT DIRECTLY UNDER THE SURGEON GENERAL. Those parts of the Army Medical Service not under the direct command of the Surgeon General, though under his technical supervision, are organized as individual services for the various military commands. Each army in the United States. each oversea theater and territorial force, and each major subordinate unit (such as an infantry division) has its own surgeon, who acts as a staff officer of the commander and supervises the medical service of the command.

Medical establishments having a more

or less fixed location in the United States and its possessions ("named" units) are distinguished from the more or less mobile units designated to serve armies in the field. The latter ("numbered" units) have a standardized form of organization and include additional varieties of units appropriate to work in the field. They may be roughly divided into three categories: (1) those whose primary purpose is to provide medical care and treatment (such as "clearing companies" and various types of hospitals echeloned farther toward the rear); (2) those whose primary purpose is to provide transportation from the battlefield, at successive stages in the "chain of evacuation" (the medical sections/platoons of battalions, regiments, or groups, motor ambulance companies, air ambulance companies, ambulance train units, etc.); and (3) certain ancillary units not directly concerned with the care or transportation of patients (depot companies, medical laboratories, and preventive medicine companies). A variety of specialized detachments (blood transfusion and storage, neuropsychiatric, surgical, dental, veterinary, supply, and administrative) also exist, whose function is to supplement or support certain principal units in the three categories just mentioned.

AGENCIES DIRECTLY UNDER THE SURGEON GENERAL. These include the following

The Office of the Surgeon General. (See chapter 2.)

Medical Centers. The Walter Reed Army Medical Center, Washington, D. C., includes Headquarters Walter Reed Army Medical Center; Walter Reed Army Hospital; Walter Reed Army Institute of Research; U. S. Army Central Dental Laboratory; U. S. Army Prosthetics Research Laboratory; U. S. Army Ocular Research Unit; U. S. Army Medical Research Unit, Malaya; U. S. Army Medical Unit, Ft. Detrick, Maryland; U. S. Army Medical Service Field Activities Unit; and U. S. Army Military Police Detachment. The Brooke Army Medical Center, Fort Sam Houston, Texas, includes Headquarters Brooke Army Medical Center; Brooke

Army Hospital; Army Medical Service School; U. S. Army Central Dental Laboratory; U. S. Army Surgical Research Unit; U. S. Army Hospital Management Research Unit; U. S. Army Medical Training Center; U. S. Army Field Medical Service Development Unit; and U. S. Army Installation Support Detachment.

Named Army Hospitals. These are Army and Navy Hospital (Hot Springs, Ark.); Fitzsimons Hospital (Denver, Colo.), which includes a U. S. Army Research and Development Unit; Valley Forge Hospital (Phoenixville, Pa.); William Beaumont Hospital (El Paso, Tex.); Letterman Hospital (San Francisco); and Madigan Hospital (Tacoma, Wash.). Army and Navy Hospital and Valley Forge Hospital include military police detachments.

Laboratories. These are the U. S. Army Environmental Health Laboratory (Army Chemical Center, Md.), U. S. Army Medical Research Laboratory (Fort Knox, Ky.), U. S. Army Medical Nutrition Laboratory (Denver, Colo.), U. S. Army Tropical Research Medical Laboratory (Fort Brooke, Puerto Rico), and Medical Equipment Development Laboratory (Fort Totten, N. Y.).

Medical Supply Installations and Activities. These are Louisville Medical Depot (Louisville, Ky.), which includes a medical depot liaison detachment and a military police detachment; Army Medical Supply Support Activity (Brooklyn, N. Y.); and U. S. Army Medical Optical and Maintenance Activity (St. Louis, Mo.).

Armed Forces Institute of Pathology. This agency, located in Washington, D. C., is the central laboratory of pathology for the Department of Defense, and for such other Federal agencies as may be agreed upon by the Secretary of Defense and the head of the agency concerned. Tissues from all important operations and all records and material from postmortem examinations performed on military personnel are sent to the Department of Pathology for diagnosis, consultation, review, or final opinion. This permits the Institute to